Advance care planning is a "process of communication among patients, their health-care providers, their families, and important others regarding the kind of care that will be considered appropriate when the patient cannot make decisions." It typically involves the use of advance directive forms outlining specific instructions, and/or the designation of a proxy decision-maker. Despite generally positive attitudes toward advance directives, few people actually complete advance directives, fewer yet understand key elements necessary for meaningful advance care planning, and even well-documented advance directives are routinely disregarded. Since the absence of planning leads to unwanted medical interventions, loss of independence, needless suffering, and financial burdens to patients, their families, and society, there is an urgent need to improve the process of advance care planning. With this study we propose to develop, refine, and evaluate a computer-based decision aid for advance care planning, through three Specific Aims: (1) To produce an interactive computer program/decision aid for helping people with the process of advance care planning. (2) To use Multi-Attribute Utility Theory (MAUT) to help users a) identify their true preferences for elements of advance care planning, and b) articulate them accurately. (3) To evaluate the computer program for ease of use, acceptability, and its effects on knowledge, attitudes, and psychological states; to assess the predictive accuracy of the MAUT model in clarifying users' values and goals. If successful, this decision aid will help to protect patients' autonomy, preserve their independence, and promote the sensible use of health-care resources.